Cams for knitting machines

ABSTRACT

POST MOUNTED CAM FORMED OF A RECTANGULAR BLOCK WHEREIN THE PROFILE OF THE CAM IS FORMED BY REMOVING PORTIONS OF ONE SIDE OF THE BLOCK TO A DEPTH LESS THAN THE DEPTH OF THE BLOCK WHEREBY THE CAM PROFILE EXTENDS UPWARDLY FROM THE SURFACE URROUNDING THE CAM PROFILE, WHEREIN A VERTICALLY EXTENDING KEYWAY ISFORMED IN THE OTHER SIDE OF THE BLOCK FOR THE FULL HEIGHT THEREOF, AND WHEREIN THE CAM BLOCK IS MOUNTED UPON ANDIS SECURED TO THE POST BY A FLAT HEAD SCREW EXTENDING THROUGH A COUNTERSUNK HOLE IN THE CAM BLOCK AND INTO THREADED ENGAGEMENT WITH THE POST. A STITCH CAM AND A GUARD CAM FORMED OF A PAIR OF BLOCKS ARE MOUNTED UPON AND ARE SECURED TO A COMMON POST BY FLAT HEAT SCREWS WITH THE CAM PROFILES SPACED FROM EACH OTHER TO PROVIDE A NEEDLE BUTT PATHWAY THEREBETWEEN AND WITH THE NEAR SIDES OF THE CAM BLOCKS PRESSED TOGETHER AND EXTENDING PERPENDICULAR TO THE POST.   D R A W I N G

Feb- 20, 1973 NoRlsHlGE sUMlToMo 3,717,013

CAMS FOR KNITTING MACHINES Filed Feb. 9, 1971 Fig.

Non uff/@5 50M/fono BY A) (L L 0M RA/MJ A TT'ORMEY United States PatentOtiice 3,717,013 Patented F eb. 20, 1973 3,717,013 CAMS FOR KNITI`INGMACHINES Norishige Sumitomo, Toyonaka, Japan, assignor to PrecisionFukuhara Works, Ltd., Higashinada Kobe City, Hyogo, Japan Filed Feb. 9,1971, Ser. No. 114,002 Claims priority, application Japan, Mar. 2, 1970,45/17,832 Int. Cl. D04b 15/32 U.S. Cl. 66-57 1 Claim ABSTRACT F THEDISCLOSURE 'Post mounted cam formed of a rectangular block wherein theprofile of the cam is formed by removing portions of one side of theblock to a depth less than the depth of the block whereby the cam proleextends upwardly from the surface surrounding the cam prole, wherein avertically extending keyway is formed in the other side of the block forthe full height thereof, and wherein the cam Iblock is mounted upon andis secured to the post by a tlat head screw extending through acountersunk hole in the cam block and into threaded engagement with thepost. A stitch cam and a guard cam formed of a pair of blocks aremounted upon and are secured to a common post by iiat heat screws withthe cam profiles spaced from each other to provide a needle butt pathwaytherebetween and with the near sides of the cam blocks pressed togetherand extending perpendicular to the post.

The present invention relates generally to the art of knitting andparticularly to the construction of post mounted cams used for themovement of needles in knitting machines.

It is the general practise to mount vertically spaced stitch and guardcams of knitting machines upon a common vertically adjustable post whichtits into keyways formed in the rear sides of each of the cams and tosecure each of the cams to the post by a single screw extending througheach cam and into threaded engagement with the post. It is desirablethat such stitch and guard cams be fully horizontally disposed, however,in this construction as the result of lateral clearance between the camkeyways and the post, because of the clearance between the screws andthe cams, and because the keyways are not etective for the full heightof the cams, it often happens that the cams are undesirably inclined tothe horizontal when secured to the post. t

It is the principal object of the present invention to provide aconstruction for post mounted cams used for the movement of needles inknitting machines wherein the cams are positively maintained in fullhorizontal disposition.

It is a further object of the present invention to form each of the camsso as to extend from one side of a rectangular block with the keywayextending for the full height of the block in the other side thereof andwherein the cam profiles of a pair of post mounted cams are spaced whilethe near sides of the pair of cam blocks are in pressure contact therebyto positively maintain said cams in full horizontal disposition.

With the above and other objects in view as will be apparent from thefollowing detailed description of preferred forms of the invention to beread in connection with the accompanying drawings, the invention residesin the construction of the post mounted cams illustrated in thedrawings, and as defined in the appended claims.

In the drawings:

FIG. 1 is a perspective view of a stitch cam of the prior art,

FIG. 2 is a perspective view of a guard cam of the prior art,

FIG. 3 is a front elevational view of the stitch cam of FIG. 1 and ofthe guard cam of FIG. 2 mounted upon and secured to a common post,

FIG. 4 is a sectional view taken along line 4-4 of FIG. 3,

FIG. 5 is a perspective view of a stitch cam of the present invention asformed with a rectangular block,

FIG. `6 is a perspective view of a guard cam of the present invention asformed with a rectangular block,

FIG. 7 is a front elevational view of the stitch cam of FIG. 5 and ofthe guard cam of FIG. 6 mounted upon and secured to a common post,

FIG. 8 is a sectional View taken along line 8-8 of FIG. 7,

FIG. 9 is a perspective view of a combined guard cam and post of thepresent invention as formed with a rectangular block,

FIG. 10 is a perspective view of a stitch cam of the present inventionas formed with a rectangular block,

FIG. Il1 is a front elevational view of the guard cam of FIG. 9 and ofthe stitch cam of FIG. 10 with the stitch cam mounted upon and securedto the post formed in combination with the guard cam, and

FIG. 12 is a sectional lview along line 12-12 of FIG. 11.

A conventionally shaped stitch cam 1 of the prior art, FIG. 1, has avertically extending square bottomed keyway 2 formed in its rear sideand has a countersunk screw receiving hole 3 extending through the camand into the keyway. A conventionally shaped guard cam 4 of the priorart, FIG. 2, has a vertically extending square bottomed keyway 5 formedin its rear side and has a countersunk screw receiving hole 6 extendingthrough the cam and into the keyway. It will be noted, in each of thecams 1 and 4, that their proles extend the full depth `or thickness ofthe stock of which the cams are made. The cams 1 and 4 areconventionally mounted, FIGS. 3 and 4, in spaced relation upon a commonvertically extending square sided post 7 which tits into keyways 2 and5. Cam 1 is secured to post 7 by a ilat head screw 8 extending throughhole 3 and into threaded engagement with post 7, and cam 4 is secured topost 7 by a at head screw 9 extending throughl hole 6 and into threadedengagement with post 7. The near faces of spaced cams 1 and 4, FIGS. 3and 4, provide a channel therebetween for the passage therethrough ofthe butts of the needles once the latter have been lowered by the actionof face 1a of cam 1 upon the needle butts.

There is normally some lateral clearance between post 7 and thesidewalls of keyways 2 and 5, and between screws 8 and 9 and holes 3 andyt5, of cams 1 and 4, respectively. One side of keyway 2 terminates atapproximately the midpoint of cam face 1a of cam 1, FIG. 3, thus onesidewall of keyway 2 is considerably shorter than the other thereof.Accordingly, when screws 8 and 9 are tightened, it often happens thatone or the other or both of cams 1 and 4, which are not in directcontact with each other, instead of being horizontal with their keywaysvertical, have been angularly located and are inclined relative to thepost 7 in the direction in which the screws have been turned and thusthe cams may be above or below the desired horizontal positions thereof.The cams may also be twisted by contact of the needle butts therewith.Such undesired positioning of the cams results in irregularity in thewidth of the butt pathway therebetween so that the needles moveirregularly and often form non uniform stitches. The distance betweencams 1 and 4 is greater than it need be for properly positioned cams andis such as to allow for irregular positioning of the cams whilestillproviding a pathway of suficient width for the needle butts. lItmay be noted that with the substantial increase in the number of feedsin multi-feed circular knitting machines, the cams are smaller and thearea of contact between the keyways and the post is accordingly reduced,thus accentuating the problem of properly positioning the cams.

A stitch cam formed as part of a rectangular block according to thepresent invention is shown at 11, FIG. 5, wherein the outline of the camprofile itself (similar to the profile of cam 1) is formed inapproximately half the depth or thickness of the block and the remaininghalf thickness of the block retains its rectangular outline. Thus thehalf thickness triangular portion of the block, which would not bepresent or which would be cut away in forming cam 1 of FIG. l, isretained, as is the portion 10a. Cam 1.1 has a vertically extendingsquare bottomed keyway 12 formed in its rear side for the full height ofthe cam blockand has a countersunk screw receiving hole 13 extendingthrough the cam and into the keyway. Cam 11 has a bottom face 14extending fully across the width of the cam perpendicular to keyway 12and spaced from hole 13.

A guard cam similarly formed as part of a rectangular block, accordingto the present invention, is shown at 16, FIG. 6, wherein the camprofile (similar to the profile of cam 4) is formed in approximatelyhalf the depth or thickness of the block and the remaining halfvthickness of the block retains its rectangular outline. Thus the fullwidth upright extension 15 of height 15a, which would not be present orwhich would be cut away in forming cam 4 of FIG. 2, is retained. Cam 16has a vertically cxtending square bottomed keyway 17 formed in its rearside for the full height of the cam block and has a countersunk screwreceiving hole 18 extending through the cam and into the keyway. Cam 16has a top face 19 extending fully across the width of the camperpendicular to keyway 17 and spaced from hole 18.

Cams-11 and 16 are mounted upon a common vertically square sided post20, FIGS. 7 and 8, which ts into keyways 12 and 17 of the cams. Cam 12is secured to post 20 by a hat head screw 21 extending through its hole13 and into threaded engagement with the post, and cam 16 is secured topost 20 =by a ilat head screw 22 extending through its hole 18 and intothreaded engagement with the post. The holes 13 and 18 of the cams andthe threaded apertures in post 20 are so disposed that when screws 21and 22 are tightened, the surfaces 14 and 19 of the cams are tightlypressed together so that the cams 11 and 16 are in fixed squaredrelationship with each other with their surfaces 14 and 19 fullyperpendicular to post 20. In this construction there is no possibilitythat the cams may be twisted whenthe screws are tightened. This will beso even though there is lateral clearance between keyways 12 and 17 and`post 20, and between holes 13 and 18 and screws 21 and 22, of the cams11 and 16, respectively, for the reason that the camming action of theconical heads of screws 21 and 22 acting upon the conical surfaces ofthe countersunk portions of holes 13 and 18 will force the cams 11 and16 together and in so doing will automaticallycause the contactingsurfaces 14 and 19 and the cams themselves to -be fully perpendicular topost 20. The keyways 12 and 17 are adjoining and are in contact with thefull length of post 20. The width of the needle butt path between thecams is determined by the height 15a of upright 15. It should be notedthat the width of the needle butt pathway between cams 11 and 16 issomewhat less than the corresponding width between cams 1 and 4 of theprior art, as may be seen by comparing FIGS. 4 and 8. This is for thereason that no allowance need be made for any twisting of the cams andaccordingly, with a narrower and more restricted butt pathway, theneedle hooks move in a. correspondingly more uniform pathway and knitmore uniform stitches.

A modified form of the invention is shown in FIG. 9 wherein a singlerectangular block is cut away to provide a guard cam 23 at the bottomportion of one side of the block and to provide a square sided post 24extending upwardly therefrom, the block being provided witha relativelynarrow shelf or ledge 25 above cam 23,1the height 25a of the ledge beingsimilar to that of upright 15 of cam 16, FIG. 6. It will be noted thatthe length of guard cam 23 is somewhat less than that of guard cams 4and 16, however, cam 23 is of suicient length to function as a guard camfor the needle butts lowered by its associated stitch cam.

Another stitch cam formed as part of a rectangular block according tothe present invention is shown at 27, FIG. 10, this cam being generallysim-ilar to cam l11, FIG. 5, except that it has a keyway 28 which iswider than keyway 12 of cam 11 in order to fit the wider post 24. Theparts 26, 29 and 30, of cam 27, are similar to the parts 10, 13 and 14,of cam 11, respectively.

The cam 27 is mounted upon post 24 which fits into its keyway 28 and thecam is secured to the post by a at headscrew 3'1 extending through hole29 and into threaded engagement with the post. In this construction, thesurface 30 of cam 27 and the top of ledge 25 are forced together by thetightening action of screw 31 (as explained in reference to the actionof screws 21, 22) so that cam 27 is in fixed squared relation to cam 23with surface 30 of `the cam fully perpendicular to the. post. The widthof the needle butt path between cams 23 and 27 is determined by theheight 25a of ledge 25 and is similar to the width of the needle buttpath between cams 11 and 16. There is likewise no possibility of cam 27being -twisted relative to post 24 when screw 31 is tightened.

lIt will be understood that the cam profiles and their associatedrectangular portions m-ay be formed from single rectangular blocks, maybe formed separately and joined together, or may be molded as a singleunit. The faces of the cams, as may be required, are curved foroperative relation to the curvature of the needle cylinder i knittinglneedles on a knitting machine, each of :said

needles having a shank and a butt extending therefrom,

each of said cams being of one piece construction, said cams beingmounted upon and secured to a lengthwise extending common post in fixedjuxtaposed relation to each other and to said post, said cams havingadjacently disposed sides of which edge portions thereof are in fixedpressed together abutting relation and which extend in perpendicularrelation to said post, a continuous keyway formed in one face of saidjuxtaposed cams for the full height of each thereof, said keywayextending across and being perpendicular to said edge portions of saidcams, said post being disposed in said keywaya single screw extendingthrough each of said cams and into threaded engagement with said post,said cams being fixedly secured to said post exclusively by saidscrews,said screws at the same time acting upon said cams to force their saidedge portions together in pressed together abutting relation wherebysaid edge portions are effectively maintained in perpendicular relationto said postvand whereby said cams are effectively maintained in fixedrelationship with each other in their said juxtaposed relation, otherportions of both of said adjacently disposed sides of said camsproviding a xed raceway therebetween in the opposite faces of said camsfor the travel 5 of said needle butts therethrough, said raceway beingof minimum width for the passage of said needle butts thereby toeffectively prevent undesirable movement of said needles transversely ofsaid raceway, and the depth of said raceway being less than thethickness of said 5 cams, said minimum width of said raceway being madepossible by reason of said construction of said cams whereby angularmovement of each of said cams about its associated screw is effectivelyprevented.

6 References Cited UNITED STATES PATENTS WILLIAM C. REYNOLDS, PrimaryExaminer

